JP7180152B2 - METHOD FOR MANUFACTURING ELECTRONIC PARTS DEVICE, HOT-PRESS SHEET AND HOT-PRESS THERMO-CURABLE RESIN COMPOSITION - Google Patents

Description

TECHNICAL FIELD The present invention relates to a method for manufacturing an electronic component device, a hot-press sheet, and a thermosetting resin composition for hot-press.

As a method for mounting electronic components on a package wiring board, flip-chip mounting, which is excellent in terms of mounting efficiency, electrical characteristics, and multi-pin compatibility, is being increasingly adopted. In flip-chip mounting, a bare chip is mounted facedown on a wiring board via bump electrodes.

For example, various small packages called CSPs (Chip Scale Packages) have been developed in order to meet the demands for higher integration, higher functionality, higher pin count, systematization, higher speed, lower cost, etc. of electronic components. The flip-chip mounting is adopted for these. In fields such as COBs (Chip on Boards), hybrid ICs (Integrated Circuits), modules, cards, etc., flip-chip mounting is employed for high-density mounting of some electronic components. Many of recent surface-mounted packages and CSPs have terminals arranged in an area array. The mounting form of this type of package is also similar to flip-chip mounting.

In the case of flip chip mounting, from the viewpoint of connection reliability and moisture resistance reliability, the gap between the electronic component and the wiring board is filled with a thermosetting underfill material, and the joint is reinforced with the hardened underfill material. and to protect the device.

As a method of interposing the underfill material between the electronic component and the wiring board, there are various methods such as a post-insertion method and a pre-application method. Among them, with the miniaturization and thinning of CSP, a method using a pre-applied underfill material for the purpose of connecting electronic parts and wiring boards and reinforcing the connection part is attracting attention ( For example, see Patent Document 1).

A TCB (Thermal Compression Bonding) process is known as a mounting method using a pre-applied underfill material. Currently, thermoplastic films are sometimes used as auxiliary films in the TCB process. This auxiliary film plays a role in preventing the pre-applied underfill material from oozing out during mounting and contaminating the crimping head.

In the conventional mounting method using a pre-applied underfill material, the mainstream is to mount each electronic component individually on the wiring board. Also, due to the increase in size, it is being considered to collectively mount a plurality of electronic components on a wiring board (see, for example, Patent Document 2). When mounting multiple electronic components on a wiring board at once, the contact state with the crimping head varies among the electronic components due to the distortion of the crimping head and the warping of the base material. The load tends to be uneven. If the load becomes non-uniform, a sufficient load may not be applied to some of the electronic components, and electrical connection between the electronic component and the board may not be possible. There is also a concern that electronic components may be damaged at locations where an excessive load is applied. A non-uniform load can also cause misalignment in the planar direction of the electronic component. If the positional deviation occurs, there is a possibility that the electrical connection between the electronic component and the substrate will be lost.

Therefore, in order to alleviate the unevenness of the load, the laminate including the electronic component and the wiring board is heated and pressed by sandwiching it between a stage and a pressure bonding head with a hot press sheet having a thermosetting resin layer interposed therebetween. A method of mounting an electronic component on a wiring board by using a wiring board has been reported (see, for example, Patent Document 3).

JP 2013-219285 A WO2017/038691 WO2017/537846

It is expected that a (meth)acrylate compound can be applied as the thermosetting resin used in the thermosetting resin layer of the hot-press sheet. However, when a hot-pressing sheet having a thermosetting resin layer containing a (meth)acrylate compound is used after being stored for a long period of time, it may become impossible to stably manufacture an electronic component device by hot-pressing.

Accordingly, an object of one aspect of the present invention is to provide a method for producing an electronic component device by hot pressing using a hot press sheet having a thermosetting resin layer containing a (meth)acrylate compound. To provide a method that enables stable production even after storage in a storage environment.

Specific means for solving the above problems include the following aspects.

One aspect of the present invention relates to a method of manufacturing an electronic component device including a wiring board and electronic components mounted on the wiring board. This method comprises a laminate having an insulating substrate, a wiring substrate having a wiring layer provided on the insulating substrate, an electronic component having a plurality of electrodes, and a bump, wherein the electronic component comprises the wiring layer and the electrode. are arranged to face each other, and the bumps are interposed between the wiring layers and the electrodes that face each other. A step of electrically connecting the wiring layer and the electrode via a bump is provided. In the step of electrically connecting the wiring layer and the electrode, the laminate and the pressure bonding head are interposed with a hot press sheet having a thermosetting resin layer. is heated and pressurized. The thermosetting resin layer contains a (meth)acrylate compound and a polymerization inhibitor. The content of the polymerization inhibitor is 0.01 to 10 parts by mass with respect to 100 parts by mass of the (meth)acrylate compound.

According to the above method, electronic component devices can be stably manufactured even after the hot-press sheet is stored for a long period of time.

The laminate may further comprise a thermosetting underfill material filling gaps between the electrodes, bumps and wiring layers between the electronic component and the wiring substrate.

In the step of electrically connecting the wiring layer and the electrode, a plurality of laminates each having one electronic component, or one or more laminates having a plurality of electronic components arranged on one wiring substrate The body may be heated and pressurized by sandwiching it between a set of stages and a crimping head. Further, the laminate may be heated and pressurized so that the temperature of the wiring board is 25°C to 200°C and the temperature of the electronic component is 230°C to 300°C.

Another aspect of the present invention relates to a hot press sheet having a thermosetting resin layer and used in the above method. The thermosetting resin layer of this hot-press sheet contains a (meth)acrylate compound and a polymerization inhibitor. The average thickness of the thermosetting resin layer may be 10 μm or more.

The hot-press sheet may further have a release sheet provided on one side or both sides of the thermosetting resin layer.

The thermosetting resin layer may further contain a filler. Moreover, the thermosetting resin layer may further contain an epoxy compound and its curing agent.

Yet another aspect of the present invention relates to a thermosetting resin composition for hot press containing a (meth)acrylate compound and a polymerization inhibitor. This curable resin composition for hot press is used to form the thermosetting resin layer of the sheet for hot press. The thermosetting resin composition may further contain a filler. In that case, the content of the filler may be 60 to 85% by mass based on the solid content of the thermosetting resin composition. The thermosetting resin composition may further contain a solvent.

According to the present invention, a laminate including an electronic component and a wiring board is sandwiched between a stage and a compression head while a hot press sheet having a thermosetting resin layer is interposed therebetween to heat and press the electronic component onto the wiring board. is mounted to manufacture an electronic component device, the electronic component device can be stably manufactured even after the hot-press sheet is stored for a long period of time. For example, even after the hot-press sheet is stored for a long period of time, it is possible to sufficiently suppress the occurrence of problems such as misalignment, poor connection, and peeling of electronic components.

FIG. 4A is a cross-sectional view showing an embodiment of a method for manufacturing an electronic component device; FIG. 4A is a cross-sectional view showing an embodiment of a method for manufacturing an electronic component device; FIG. 4A is a cross-sectional view showing an embodiment of a method for manufacturing an electronic component device; 1 is a cross-sectional view of an electronic component device according to one embodiment; FIG. 1 is a cross-sectional view of a hot-press sheet according to one embodiment; FIG.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described with appropriate reference to the drawings. However, the present invention is not limited to the following embodiments. In the following embodiments, the constituent elements (including element steps and the like) are not essential unless otherwise specified. The same applies to numerical values and their ranges, which do not limit the present invention. In addition, the sizes of the members in each drawing are conceptual, and the relative relationship between the sizes of the members is not limited to this.

In this specification, the numerical range indicated using "-" includes the numerical values before and after "-" as the minimum and maximum values, respectively.
In the numerical ranges described stepwise in this specification, the upper limit or lower limit described in one numerical range may be replaced with the upper limit or lower limit of the numerical range described in other steps. good. In the numerical ranges described herein, the upper or lower limits of the numerical ranges may be replaced with the values shown in the examples.
In the present specification, the content of each component in the composition is the total of the multiple substances present in the composition when there are multiple substances corresponding to each component in the composition, unless otherwise specified. means the content of
As used herein, the particle size of each component in the composition refers to a mixture of the plurality of types of particles present in the composition when there are multiple types of particles corresponding to each component in the composition, unless otherwise specified. means a value for
In this specification, the term "layer" refers to the case where the layer is formed in the entire region when the region where the layer exists is observed, and the case where the layer is formed only in a part of the region. is also included.
As used herein, "average thickness", "average distance", and "average width" mean the arithmetic average value of measurements at three arbitrarily selected points.
As used herein, the term "process" includes a process that is independent of other processes, and even if the purpose of the process is achieved even if it cannot be clearly distinguished from other processes. be

<Method for manufacturing an electronic component device>
An example of the manufacturing method of this embodiment will be described below with reference to FIGS. In the method according to the embodiment shown in FIGS. 1 to 3, after the underfill material is applied in advance to the surface of the electronic component facing the wiring board, the electrodes of the electronic component and the wiring layer of the wiring board are interposed through the bumps. are electrically connected.

(Addition process)
First, as shown in FIG. 1, electrodes of an electronic component 20 having a main body 21, a plurality of electrodes 23 provided on one main surface of the main body 21, and bumps 25 provided on the electrodes 23, respectively. An underfill material 30 is applied to the surface on the side of 23 and bump 25 (applying step).

Electronic component 20 may be, for example, a semiconductor chip. The type of electronic components is not particularly limited, and may be a die (chip) itself that is not packaged with resin or the like, a CSP that is packaged with resin or the like, a semiconductor package called BGA (Ball Grid Array), or the like. There may be.

The material of the bumps 25 is not particularly limited, and can be selected from commonly used materials such as solder. The bumps may be a combination of metal posts and solder. From the viewpoint of environmental concerns and safety, the bumps may be made of Cu or Au, as well as lead-free solder such as Ag--Cu solder, Sn--Cu solder, and Sn--Bi solder. When the bumps are formed from lead-free solder, minute gaps tend to occur around the bumps due to poor wetting of the lead-free solder. However, according to the manufacturing method of the present embodiment, even when lead-free solder is used for bumps, it is possible to effectively suppress the occurrence of misalignment.

(Contact process)
Next, as shown in FIG. 2, the electronic component 20 provided with the underfill material 30 is placed on the temporary pressure bonding head 42, and the electronic component 20 and the insulating substrate 11 and the insulating substrate 11 placed on the stage 41 are placed. The wiring substrate 10 having the wiring layer 13 provided thereon is opposed. Then, the electronic component 20 and the wiring board 10 are heated and pressed by the stage 41 and the temporary pressure bonding head 42 , and thereby the electrodes 23 , the bumps 25 and the wiring layer 13 are compressed between the electronic component 20 and the insulating substrate 11 . The underfill material 30 is filled in the gap between the bumps 25 and the wiring layer 13 (contact step).

The type of the insulating substrate 11 is not particularly limited, and for example, organic substrates containing fiber base materials such as FR4 and FR5, build-up type organic substrates not containing fiber base materials, organic films such as polyimide and polyester, and alumina, It can be selected from substrates including inorganic substrates of glass, silicon. When a substrate containing silicon is used as the substrate, a through electrode (through silicon via; TSV (Through Silicon Via)) may be formed in the substrate.

The wiring layer 13 is normally a conductor wiring including electrodes for connection. The wiring layer 13 is formed by, for example, a semi-additive method, a subtractive method, or the like.

The underfill material can be applied to at least one of the surface of the electronic component 20 on the electrode 23 side and the surface of the wiring substrate 10 on the wiring layer 13 side. From the viewpoint of productivity, it is preferable to apply the underfill material only to the electronic component 20 . A bump may be provided on the wiring layer 13 of the wiring substrate 10 .

As the underfill material 30, a conventionally used underfill material can be used. For example, JP-A-2013-151642, JP-A-2013-219285, JP-A-2015-032637, JP-A-2015-032638, JP-A-2015-083633, and JP-A-2015-083634 Underfill materials described in can be used.

The shape of the underfill material is not particularly limited, and may be film-like or liquid-like. The shape of the underfill material is preferably film-like from the viewpoint of suppressing positional deviation in the plane direction between the electronic component and the wiring board in the pressing step. From the viewpoint of connection reliability when the pitch between adjacent connection portions becomes narrower, the underfill material preferably does not contain conductive particles.

The method of applying the underfill material to the surface of the electronic component 20 on the electrode 23 side (or the surface of the wiring substrate 10 on the wiring layer 13 side) is not particularly limited.

When the underfill material is liquid, examples of application methods include a screen printing method and a method using a dispenser such as an air dispenser, a jet dispenser, and an auger type dispenser.

When the underfill material is in the form of a film, examples of the application method include a method using a diaphragm type laminator, a roll type laminator, and the like.

The application shape of the underfill material is not particularly limited. When applying the underfill material on the wiring board, for example, a method of applying the underfill material to the entire mounting position of the electronic component, a cross shape consisting of two lines along the diagonal line of a square corresponding to the mounting position of the electronic component. The underfill material is applied by a method of applying the underfill material, a method of applying the underfill material in an American shape obtained by overlapping the cross shape with the cross shape shifted by 45°, or a method of applying the underfill material at one point at the center of the mounting position of the electronic component. In order to suppress creeping of the underfill material from the viewpoint of reliability, it is preferable to apply the underfill material in the shape of a cross or an American letter. When the wiring substrate is provided with substrate electrodes (or wiring layers), it is preferable to apply the underfill material to the mounting positions of the electronic components, including the locations where the substrate electrodes are provided.

When applying a film-like underfill material, it is desirable to apply the underfill material to the entire surface of the electronic component facing the wiring board or the entire position of the wiring board where the electronic component is mounted.

The temperature at which the underfill material is applied can be selected according to the properties of the underfill material. When a film-like underfill material is applied to an electronic component by a diaphragm type laminator, it is preferable that the temperature of the underfill material and the surface of the electronic component is, for example, 50 ° C. to 100 ° C., and voids during lamination From the viewpoint of suppressing entanglement, it is more preferable to set the temperatures to 70° C. to 90° C., and more preferably to around 80° C.

The temperature of the underfill material in the contact step (hereinafter also referred to as "filling temperature") is preferably lower than the curing temperature of the underfill material. For example, the filling temperature of the underfill material is preferably less than 200°C. By setting the filling temperature of the underfill material to be less than 200° C., when the underfill material is filled into the gap between the electronic component and the wiring board by pressurization, the underfill material can be prevented from increasing in viscosity, and the underfill material can be The fluidity of the material becomes sufficient, the connection tends to be easily secured, and the occurrence of voids can be avoided.

The lower limit of the filling temperature of the underfill material is not particularly limited. From the viewpoint of lowering the viscosity of the underfill material, the filling temperature of the underfill material is, for example, preferably 30° C. or higher, more preferably 50° C. or higher, and even more preferably 80° C. or higher. .

A specific method for adjusting the filling temperature of the underfill material is not particularly limited. For example, a method of adjusting the temperature of at least one of the electronic component and the wiring board to the filling temperature and bringing it into contact with the underfill material can be used.

In the contact process, the magnitude of the pressure applied to the wiring board and the electronic component device by the stage and the temporary pressure bonding head varies, as in the general flip chip mounting process, due to variations in the number or height of bumps, bumps due to pressure, or It can be set in consideration of the amount of deformation of the wiring provided on the insulating substrate that receives the bumps. Specifically, for example, it is preferable that the load applied to each bump is set to about 1 g to 10 g. Also, for example, it is preferable to set the load applied to one chip to approximately 10N to 100N.

(Connection process)
Next, as shown in FIG. 3, the three laminates 5 composed of the electronic component 20, the wiring board 10, and the underfill material 30 therebetween are placed between the laminate 5 and the crimping head 43 by heat. Heat and pressure are applied by the stage 41 and the pressure bonding head 43 while interposing the hot press sheet 3 having a curable resin layer. By this heating and pressing, the electrodes 23 of the electronic component 20 and the wiring layers 13 of the wiring board 10 are electrically connected via the bumps 25, and the underfill material 30 is cured (connecting step). Usually, the thermosetting resin layer of the hot-press sheet is also cured in this connecting step.

From the viewpoint of ensuring connection between the electronic component and the wiring board via the bumps, the connecting step is preferably performed at a temperature equal to or higher than the melting point of the bumps. That is, it is preferable that the temperature be such that metal bonding is formed between the bumps and the wiring or the like on the insulating substrate. For example, if the bumps are solder bumps, the connecting process is preferably performed at a temperature of 230° C. or higher. From the viewpoint of heat resistance of the underfill material, the connecting step is preferably performed at a temperature of, for example, 320° C. or lower, and more preferably at a temperature of 300° C. or lower. Solder connection requires a higher temperature than connection methods using conductive particles, but it has high connection reliability. This connection method can also be applied when From the above point of view, it is preferable that the laminated body 5 is heated and pressurized so that the temperature of the wiring board 10 is 25 to 200.degree. C. and the temperature of the electronic component 20 is 230 to 300.degree. The hot press sheet 3 used for heating and pressing at such high temperatures preferably has heat resistance of 200° C. or more. The details of the hot press sheet 3 having such heat resistance will be described later.

In the connection process, the number of electronic components, wiring boards, and laminates including these that are collectively heated and pressurized by one set of stages and pressure bonding heads is not particularly limited. From the viewpoint of production efficiency, it is preferable to collectively heat and press a plurality of electronic components and/or a plurality of laminates. In that case, one hot-press sheet may be arranged for each electronic component or laminate, or one hot-press sheet may be arranged so as to cover a plurality of electronic components. From the viewpoint of production efficiency, it is preferable to arrange one resin sheet so as to cover a plurality of electronic components.

The number of electronic components or laminates that are collectively heated and pressurized is, for example, preferably 2 or more, more preferably 3 or more, and further preferably 5 or more. preferable. The effect of the manufacturing method of the present embodiment is more remarkable as the number of electronic components or laminates to be collectively heated and pressurized increases. The upper limit of the number of electronic components or laminates that are collectively heated and pressurized is not particularly limited, but may be, for example, 100 or less.

From the viewpoint of production efficiency, the connecting step is preferably performed in a short time. Specifically, for example, the temperature increase rate is preferably 5° C./second or more, more preferably 10° C./second or more, and even more preferably 15° C./second or more. The heating time varies depending on the type of material forming the bumps, but from the viewpoint of production efficiency, the shorter the heating time, the better. When the bumps are solder bumps, the heating time is, for example, preferably 30 seconds or less, more preferably 20 seconds or less, and even more preferably 10 seconds or less. In the case of Cu--Cu or Cu--Au metal bonding, the heating time is preferably 30 seconds or less, for example.

From the viewpoint of suppressing misalignment between the electronic component and the wiring board in the connecting step, the curing speed of the thermosetting resin layer of the hot-press sheet is preferably faster than the curing speed of the underfill material. By making the curing speed of the thermosetting resin layer of the hot-press sheet faster than the curing speed of the underfill material, thermal expansion during heating is further suppressed, which tends to make it easier to suppress misalignment.

Through the above steps, three electronic component devices 1 shown in FIG. 4 are collectively manufactured. Conventionally, when a plurality of electronic component devices are manufactured collectively in this way, the contact state between the crimping head and the electronic component varies among the electronic components, resulting in uneven loads during heating and pressing, resulting in Many connection failures of the device occurred, and the yield was sometimes lowered. An uneven load can contribute to a decrease in the reliability of the electronic component device even if it does not cause poor connection of the electronic component device.

On the other hand, according to the manufacturing method of the present embodiment using the hot press sheet, even when a plurality of electronic component devices are collectively manufactured, the contact state between the electronic component and the pressure bonding head does not vary. is reduced, the load non-uniformity is reduced, and as a result, the yield is improved. The reason for this can be considered, for example, as follows.

By interposing the hot-pressing sheet between the pressure-bonding head and the electronic component, the thermal expansion of the pressure-bonding head and the electronic component is suppressed by curing the thermosetting resin layer of the hot-pressing sheet. It is thought that the positional deviation due to the difference and the positional deviation due to the force in the surface direction applied from the crimping head with insufficient parallelism are suppressed. Further, for example, when a plurality of electronic component devices are collectively manufactured, even if the contact state with the pressure bonding head varies among the electronic components, the gap between the pressure bonding head and the electronic component can be filled with the hot press sheet. be able to. In this state, the thermosetting resin layer of the hot-press sheet hardens, and as a result, unevenness in the load applied to the electronic component and the wiring board is reduced, and misalignment is suppressed.

In addition, by suppressing the formation of voids in the hot-press sheet of the present embodiment, it is possible to further suppress the reduction in thermal conductivity and the uniformity of the load applied to the electronic component via the hot-press sheet. . Thereby, it is possible to more stably collectively manufacture a plurality of electronic component devices.

<Electronic parts equipment>
The electronic component device 1 shown in FIG. 4 includes a wiring substrate 10 having an insulating substrate 11 and a wiring layer 13 provided on the insulating substrate 11, an electronic component 20 having a plurality of electrodes 23, a plurality of bumps 25, and a hardened underfill material 30 . Electronic component 20 is arranged such that electrode 23 and wiring layer 13 face each other, and bump 25 is interposed between facing electrode 23 and wiring layer 13 . The electrodes 23 and the wiring layers 13 are electrically connected by bumps 25 . The underfill material 30 fills the gaps formed between the electrodes 23 , the bumps 25 and the wiring layer 13 between the electronic component 20 and the wiring board 10 . The electronic component device 1 of this embodiment has good connectivity between the electronic component and the wiring board, and is excellent in reliability.

The effect of the method of this embodiment is particularly remarkable when manufacturing an electronic component device in which the distance between the electronic component and the wiring board and the distance between bumps are small. Specifically, the average distance between the electronic component and the wiring board in the electronic component device is, for example, preferably 50 μm or less, more preferably 40 μm or less, and even more preferably 30 μm or less. Also, the average distance between adjacent bumps is, for example, preferably 200 μm or less, more preferably 150 μm or less, even more preferably 100 μm or less, and particularly preferably 80 μm or less.

In the present embodiment, the wiring substrate may have uneven portions formed by wiring patterns and resist patterns on an insulating substrate. When the wiring board has a wiring pattern and a resist pattern, for example, the wiring pattern has an average width of 50 μm to 300 μm, the resist opening has an average width of 50 μm to 150 μm, and the resist has an average thickness of 10 μm to 20 μm. is preferred. The wiring pattern includes wiring layers connected to the bumps.

According to the manufacturing method of the present embodiment, it is possible to suppress misalignment between the electronic component and the substrate even when the substrate having the uneven portion as described above is used.

<Sheet for heat press>
The hot-press sheet used in the method according to the present embodiment has a thermosetting resin layer that is cured by heating. FIG. 5 is a cross-sectional view showing a hot-press sheet according to one embodiment. The hot press sheet 3 shown in FIG. 5 has a thermosetting resin layer 31 and release sheets 33 a and 33 b provided on both sides of the thermosetting resin layer 31 . The thermosetting resin layer 31 is formed by molding a thermosetting resin composition into a sheet. A release sheet may be provided on one side of the thermosetting resin layer.

When mounting the electronic component on the wiring board by heating the electronic component with the crimping head, by interposing the hot press sheet of the present embodiment between the crimping head and the electronic component, the electronic component and the substrate are bonded together. It is possible to suppress positional deviation and collectively manufacture a plurality of electronic component devices. Hereinafter, each component and configuration of the hot-press sheet of the present embodiment will be described in detail.

[Release sheet]
The release sheets 33a and 33b are sheets having releasability such that they do not stick to the pressure bonding head and the laminate after heating and pressurizing the laminate. It is preferable that the release sheets 33a and 33b are provided for easy mold release. It doesn't have to be. Examples of the support include polyethylene films, polyolefin films such as polyvinyl chloride, polyethylene terephthalate films, polyethylene naphthalate films, polycarbonate films, polyimide films and other organic resin films; release paper; and metals such as copper foil and aluminum foil. foil. From the viewpoint of heat resistance, the support is preferably a polyimide film, or a metal foil such as a copper foil or an aluminum foil.

As the release sheet, the electrical The release sheet that comes into contact with the electronic component when it is physically connected may have a release layer formed by applying a release agent. Release agents used to form the release layer include non-silicone release agents such as alkyd resins, melamine resins, olefin resins and urethane resins, silicone release agents, PTFE (polytetrafluoroethylene), and PFA. (perfluoroalkoxy fluororesin), FEP (tetrafluoroethylene/hexafluoropropylene copolymer), ETFE (ethylene/tetrafluoroethylene copolymer), ECTFE (ethylene/chlorotrifluoroethylene copolymer), PVDF (polyvinylidene fluoride) and the like, and the like.

Examples of commercially available releasing agents include "X" (silicone-containing alkyd resin-based releasing agent; 490 mN/20 mm) and "SK-1" (silicone-containing alkyd resin-based releasing agent; 1250mN/20mm), "AL-5" (non-silicone/alkyd resin release agent; 1480mN/20mm), "6050" (non-silicone/alkyd resin release agent; 2400mN/20mm), "6051" (non- silicone/alkyd resin release agent; 2800 mN/20 mm), and "6052" (non-silicone/alkyd resin release agent; 4000 mN/20 mm) (values in parentheses are initial adhesion strength values ).
In addition, commercially available release agents include, for example, "AL-7" (non-silicone/alkyd resin release agent; heavy release type) manufactured by Lintec Corporation, and "NSP" manufactured by Fujimori Industry Co., Ltd. -4” (non-silicone/alkyd resin release agent; heavy release type). Further, commercial release agents include, for example, the Tesfine series (Tesfine 303, Tesfine 305, Tesfine 314, Tesfine 319, and TA31-209E) manufactured by Hitachi Chemical Co., Ltd.

The average thickness of the hot press sheet including the release sheet is preferably, for example, 20 μm to 400 μm. The thickness of the thermosetting resin layer or hot press sheet can be measured using a micrometer.

[Thermosetting resin layer]
The average thickness of the thermosetting resin layer 31 is preferably 10 μm or more, more preferably 20 μm or more, and more preferably 30 μm or more, from the viewpoint of suppressing misalignment in the plane direction between the electronic component and the wiring board. It is even more preferable to have The average thickness of the thermosetting resin layer 31 is, for example, preferably 300 μm or less, more preferably 200 μm or less, even more preferably 100 μm or less, and less than 20 μm, from the viewpoint of film formation. is particularly preferred.

The thermosetting resin layer 31 or the thermosetting resin composition for forming this contains a (meth)acrylate compound and a polymerization initiator, and may further contain other components if necessary.

The curing reaction of the thermosetting resin ((meth)acrylate compound) contained in the thermosetting resin layer may proceed to some extent before the hot-pressing sheet is used for hot-pressing by the stage and the pressure bonding head. As a result, even when there is a large variation in the thickness of the electronic component, a more remarkable effect can be obtained in terms of eliminating unevenness in the load. For example, the curing reaction of the thermosetting resin can be advanced to some extent by adjusting the drying conditions for forming the thermosetting resin layer, or by heat treatment or ultraviolet irradiation.

The progress of the curing reaction of the thermosetting resin layer can be estimated based on the melt viscosity of the thermosetting resin layer. Specifically, the thermosetting resin layer may have a minimum melt viscosity of 1,000 to 100,000 Pa·s in the temperature range of 25°C to 180°C. When the minimum melt viscosity is 1,000 or more, the resin layer does not excessively flow in the hot-press sheet that has been deformed to eliminate load non-uniformity, and the shape is easily maintained. When the minimum melt viscosity is 100,000 or less, the hot-press sheet tends to be easily deformed so as to eliminate uneven load. From the same point of view, the thermosetting resin layer may have a minimum melt viscosity of 5,000 to 50,000 Pa·s, or 10,000 to 30,000 Pa·s in the temperature range of 25°C to 180°C. The minimum melt viscosity of the thermosetting resin layer is the viscosity (complex viscosity). The viscosity (complex viscosity) can be measured using, for example, a rheometer (dynamic viscoelasticity measuring device, device name: MCR301, manufactured by Anton Paar Japan Co., Ltd.).

(Meth)acrylate compound The (meth)acrylate compound is a monofunctional (meth)acrylate having one (meth)acrylate group, a polyfunctional (meth)acrylate compound having two or more (meth)acrylate groups, or a combination thereof. can be A "(meth)acrylate group" means a methacrylate group or an acrylate group. Examples of the (meth)acrylate compound include erythritol poly(meth)acrylate, a (meth)acrylate compound having a glycidyl ether group, a di(meth)acrylate compound having a diol unit derived from bisphenol A, and a di(meth)acrylate compound having a cyclodecane group. meth)acrylate compound, methylol (meth)acrylate, glycol di(meth)acrylate, di(meth)acrylate compound having a dioxane group, (meth)acrylate compound having a diol unit derived from bisphenol F, dimethylol (meth)acrylate, Isocyanuric acid di(meth)acrylate, and trimethyloltri(meth)acrylate. Among them, trimethylol tri(meth)acrylate, an isocyanuric acid di(meth)acrylate compound, a (meth)acrylate compound having a diol unit derived from bisphenol F, a di(meth)acrylate compound having a cyclodecane group, and a glycidyl ether group. At least one selected from the group consisting of (meth)acrylate compounds having These (meth)acrylate compounds may be used alone or in combination of two or more.

The content of the (meth)acrylate compound in the thermosetting resin layer and the thermosetting resin composition for forming the same is not particularly limited, but from the viewpoint of obtaining sufficient curability, the thermosetting resin layer, Or, for example, it is preferably 30% by mass or more, more preferably 40% by mass or more, relative to the mass of the solid content of the thermosetting resin composition. From the viewpoint of fluidity of the thermosetting resin layer, the content of the (meth)acrylate compound is, for example, 99% by mass with respect to the mass of the solid content of the thermosetting resin layer or the thermosetting resin composition. or less, more preferably 95% by mass or less, and even more preferably 70% by mass or less.

The thermosetting resin layer may further contain other thermosetting resins, that is, other compounds having reactive functional groups that form crosslinked structures to cure the thermosetting resin layer. Examples of other thermosetting resins include epoxy compounds, bismaleimide compounds, cyanate compounds, and phenol compounds. Thermosetting resins may be used singly or in combination of two or more.

Epoxy compounds that can be used as other thermosetting resins are not particularly limited as long as they are compounds having two or more epoxy groups in one molecule. Epoxy compounds commonly used for the manufacture of electronic components can be used. Examples of epoxy compounds include glycidyl ether type epoxy resins obtained by reacting bisphenol A, bisphenol F, bisphenol AD, bisphenol S, naphthalenediol, hydrogenated bisphenol A, etc. with epichlorohydrin; Novolac type epoxy resin obtained by epoxidizing novolak resin obtained by condensing or copolymerizing a phenol compound and an aldehyde compound; Glycidyl ester type epoxy resin obtained by reacting polybasic acid such as phthalic acid and dimer acid with epichlorohydrin ; Glycidylamine type epoxy resins obtained by reacting amine compounds such as p-aminophenol, diaminodiphenylmethane and isocyanuric acid with epichlorohydrin; Linear aliphatic epoxy resins obtained by oxidizing olefin bonds with peracids such as peracetic acid and alicyclic epoxy resins. These epoxy compounds may be used singly or in combination of two or more. Bisphenol-type epoxy resins and glycidylamine-type epoxy resins are preferred from the viewpoint of reactivity and heat resistance.

The epoxy compound may be solid or liquid, and a solid epoxy compound and a liquid epoxy compound may be used in combination. A liquid epoxy compound is preferable from the viewpoint of lowering the viscosity of the thermosetting resin composition.

Polymerization inhibitors Regardless of the presence or absence of a radical polymerization initiator (described later), (meth)acrylate compounds may undergo radical polymerization during storage due to the effects of heat, oxygen, etc., and this affects the stability of electronic device manufacturing. there is a possibility. It is believed that the combination of the (meth)acrylate compound with the polymerization inhibitor improves the stability of the electronic component device production. The polymerization inhibitor is not particularly limited as long as it has an effect of inhibiting radical polymerization. The polymerization inhibitor may be, for example, a phenol-based, phosphorus-based, or thioether-based polymerization inhibitor, or a combination thereof.

Phenolic polymerization inhibitors include, for example, pentaerythrityl-tetrakis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 3,9-bis{2-[3-(3 -t-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}2,4,8,10-tetraoxaspiro[5,5]undecane, octadecyl-3-(3, 5-di-t-butyl-4-hydroxyphenyl)propionate, 1,6-hexanediol-bis[3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 1,3,5 -trimethyl-2,4,6-tris(3,5-di-t-butyl-4-hydroxybenzyl)benzene, 2,6-di-t-butyl-4-methylphenol, 2,6-di-t -butyl-4-ethylphenol, 2,6-diphenyl-4-octadecyloxyphenol, stearyl (3,5-di-t-butyl-4-hydroxyphenyl) propionate, distearyl (3,5-di-t -butyl-4-hydroxybenzyl)phosphonate, thiodiethylene glycol bis[(3,5-di-t-butyl-4-hydroxyphenyl)propionate], 4,4'-thiobis(6-t-butyl-m-cresol) , 2-octylthio-4,6-di(3,5-di-t-butyl-4-hydroxyphenoxy)-s-triazine, 2,2′-methylenebis(4-methyl-6-t-butyl-6- butylphenol), 2,-2'-methylenebis(4-ethyl-6-t-butylphenol), bis[3,3-bis(4-hydroxy-3-t-butylphenyl)butyric acid]glycol ester, 4, 4'-butylidenebis(6-t-butyl-m-cresol), 2,2'-ethylidenebis(4,6-di-t-butylphenol), 2,2'-ethylidenebis(4-s-butyl-6 -t-butylphenol), 1,1,3-tris(2-methyl-4-hydroxy-5-t-butylphenyl)butane, bis[2-t-butyl-4-methyl-6-(2-hydroxy- 3-t-butyl-5-methylbenzyl)phenyl]terephthalate, 1.3.5-tris(2,6-dimethyl-3-hydroxy-4-t-butylbenzyl)isocyanurate, 1,3,5-tris (3,5-di-t-butyl-4-hydroxybenzyl)-2,4,6-trimethylbenzene, 1,3, 5-tris[(3,5-di-t-butyl-4-hydroxyphenyl)propionyloxyethyl]isocyanurate, tetrakis[methylene-3-(3,5-di-t-butyl-4-hydroxyphenyl)propionate ] Methane, 2-t-butyl-4-methyl-6-(2-acryloyloxy-3-t-butyl-5-methylbenzyl)phenol, 3,9-bis(1,1-dimethyl-2-hydroxyethyl )-2,4-8,10-tetraoxaspiro[5,5]undecane-bis[β-(3-t-butyl-4-hydroxy-5-methylphenyl)propionate], triethylene glycol bis[β- (3-t-butyl-4-hydroxy-5-methylphenyl)propionate], 1,1′-bis(4-hydroxyphenyl)cyclohexane, 2,2′-methylenebis(4-methyl-6-t-butylphenol), 2,2'-methylenebis(4-ethyl-6-t-butylphenol), 2,2'-methylenebis(6-(1-methylcyclohexyl)-4-methylphenol), 4,4'-butylidenebis(3-methyl-6 -t-butylphenol), 3,9-bis(2-(3-t-butyl-4-hydroxy-5-methylphenylpropionyloxy)1,1-dimethylethyl)-2,4,8,10-tetraoxaspiro ( 5,5) Undecane, 4,4'-thiobis(3-methyl-6-t-butylphenol), 4,4'-bis(3,5-di-t-butyl-4-hydroxybenzyl)sulfide, 4,4'- Thiobis(6-t-butyl-2-methylphenol), 2,5-di-t-butylhydroquinone, 2,5-di-t-amylhydroquinone, 2-t-butyl-6-(3-t-butyl-2-hydroxy-5 -methylbenzyl)-4-methylphenyl acrylate, 2,4-dimethyl-6-(1-methylcyclohexyl, styrenated phenol, and 2,4-bis((octylthio)methyl)-5-methylphenol. Among these, hindered phenols are preferred.

Phosphorus-based polymerization inhibitors include, for example, bis-(2,6-di-t-butyl-4-methylphenyl)pentapentaerythritol diphosphite, tris(2,4-di-t-butylphenyl phosphite ), tetrakis(2,4-di-t-butyl-5-methylphenyl)-4,4′-biphenylenediphosphonite, 3,5-di-t-butyl-4-hydroxybenzylphosphonate-diethyl ester, bis-( 2,6-dicumylphenyl)pentaerythritol diphosphite, 2,2-methylenebis(4,6-di-t-butylphenyl)octylphosphite, tris(mono- or di-nonylphenylphosphite), bis(2 ,4-di-t-butylphenyl)pentapentaerythritol-di,-phosphite, bis(2,6-di-t-butyl-4-methoxycarbonylethyl-phenyl)pentaerythritol diphosphite, and bis(2 ,6-di-t-butyl-4-octadecyloxycarbonylethyl-phenyl)pentaerythritol diphosphite.

Examples of thioether-based polymerization inhibitors include dilauryl 3,3′-thiodipropionate, bis(2-methyl-4-(3-n-dodecyl)thiopropionyloxy)-5-t-butylphenyl)sulfide, Distearyl-3,3'-thiodipropionate, and pentaerythritol-tetrakis(3-lauryl)thiopropionate.

One or a combination of two or more selected from the polymerization inhibitors exemplified above can be used.

The content of the polymerization inhibitor in the thermosetting resin layer and the thermosetting resin composition for forming the same is 0.01 to 10 parts by mass with respect to 100 parts by mass of the (meth)acrylate compound content. preferably 0.1 to 5 parts by mass. When the content of the polymerization inhibitor is within this range, it is easy to obtain sufficient storage stability of the hot-press sheet while ensuring the polymerization reaction rate.

Radical polymerization initiator The thermosetting resin layer and the thermosetting resin composition for forming the same may further contain a radical polymerization initiator. The radical polymerization initiator is typically a thermal radical polymerization initiator, and may be a combination of a thermal radical polymerization initiator and a photoradical polymerization initiator. Thermal radical polymerization initiators include, for example, ketone peroxides, hydroperoxides, diacyl peroxides, dialkyl peroxides, peroxyketals, alkyl peresters (peroxyesters), and peroxycarbonates. One of these radical polymerization initiators may be used alone, or two or more thereof may be used in combination.

Specific examples of ketone peroxides include methyl ethyl ketone peroxide, methyl isobutyl ketone peroxide, acetylacetone peroxide, cyclohexanone peroxide, and methylcyclohexanone peroxide.

Specific examples of hydroperoxides include 1,1,3,3-tetramethylbutyl hydroperoxide, cumene hydroperoxide, t-butyl hydroperoxide, p-menthane hydroperoxide, and diisopropylbenzene hydroperoxide. mentioned.

Specific examples of diacyl peroxide include diisobutyryl peroxide, bis-3,5,5-trimethylhexanol peroxide, dilauroyl peroxide, dibenzoyl peroxide, m-toluylbenzoyl peroxide, and succinic acid peroxide. mentioned.

Specific examples of dialkyl peroxide include dicumyl peroxide, 2,5-dimethyl-2,5-bis(t-butylperoxy)hexane, 1,3-bis(t-butylperoxyisopropyl)hexane, t-butyl Cumyl peroxide, di-t-butyl peroxide, di-t-hexyl peroxide, and 2,5-dimethyl-2,5-bis(t-butylperoxy)hexyne-3.

Specific examples of peroxyketals include 1,1-bis(t-hexylperoxy)-3,3,5-trimethylcyclohexane, 1,1-bis(t-hexylperoxy)cyclohexane, 1,1-bis (t-butylperoxy)-2-methylcyclohexane, 1,1-bis(t-butylperoxy)cyclohexane, 2,2-bis(t-butylperoxy)butane, and 4,4-bis(t- Butyl peroxy)pentanoate.

Specific examples of alkyl peresters (peroxyesters) include 1,1,3,3-tetramethylbutyl peroxyneodecanoate, α-cumyl peroxyneodecanoate, and t-butyl peroxyneodecano. ate, t-hexylperoxyneodecanoate, t-butylperoxyneoheptanoate, t-hexylperoxypivalate, t-butylperoxypivalate, 1,1,3,3-tetramethylbutylper Oxy-2-ethylhexanoate, t-amylperoxy-2-ethylhexanoate, t-butylperoxy-2-ethylhexanoate, t-butylperoxyisobutyrate, di-t-butylper Oxyhexahydroterephthalate, 1,1,3,3-tetramethylbutylperoxy-3,5,5-trimethylhexanoate, t-amylperoxy 3,5,5-trimethylhexanoate, t-butylperoxy -3,5,5-trimethylhexanoate, t-butylperoxyacetate, t-butylperoxybenzoate, dibutylperoxytrimethyladipate, 2,5-dimethyl-2,5-di-2-ethylhexanoylper Oxyhexane, t-hexylperoxy-2-ethylhexanoate, t-hexylperoxyisopropyl monocarbonate, t-butylperoxylaurate, t-butylperoxyisopropylmonocarbonate, t-butylperoxy-2- Ethylhexyl monocarbonate, and 2,5-dimethyl-2,5-di-benzoylperoxyhexane.

Specific examples of peroxycarbonate include di-n-propylperoxydicarbonate, diisopropylperoxycarbonate, di-4-t-butylcyclohexylperoxycarbonate, di-2-ethylhexylperoxycarbonate, and di-sec-butyl. Peroxycarbonate, di-3-methoxybutylperoxydicarbonate, di-2-ethylhexylperoxydicarbonate, diisopropyloxydicarbonate, t-amylperoxyisopropylcarbonate, t-butylperoxyisopropylcarbonate, t-butylperoxydicarbonate Oxy-2-ethylhexyl carbonate, and 1,6-bis(t-butylperoxycarboxyloxy)hexane.

Among these thermal radical polymerization initiators, cyclohexane-type peroxides such as 1,1-bis(t-butylperoxy)cyclohexane are preferable from the viewpoint of curability.

The content of the radical polymerization initiator in the thermosetting resin layer and the thermosetting resin composition for forming the same is 0.0 to 10 parts by mass with respect to 100 parts by mass of the (meth)acrylate compound content. and more preferably 0.1 to 5 parts by mass.

Filler The thermosetting resin layer and the thermosetting resin composition for forming the same may further contain a filler. Fillers can be inorganic fillers, organic fillers, or combinations thereof.

Examples of inorganic fillers include silica particles such as fused silica and crystalline silica; particles such as calcium carbonate, clay, and alumina; silicon nitride, silicon carbide, boron nitride, calcium silicate, potassium titanate, aluminum nitride, beryllia, and zirconia. , zircon, forsterite, steatite, spinel, mullite, titania, etc.; beads obtained by spheroidizing these particles; and glass fibers. These inorganic fillers may be used alone or in combination of two or more.

The thermosetting resin layer and the thermosetting resin composition for forming the same may contain at least one organic filler. Examples of organic fillers include rubber particles, polyamide fine particles, and silicone particles. Moreover, the preferred content and average particle size of the organic filler are the same as those of the inorganic filler described above.

The volume-average particle size of the filler is, for example, preferably in the range of 0.01 μm to 20 μm, more preferably in the range of 0.3 μm to 10 μm. When the volume average particle diameter of the filler is 0.01 μm or more, the viscosity of the thermosetting resin composition tends to be easily adjusted by adjusting the amount of the filler added. When the volume average particle size of the filler is 10 μm or less, it tends to be possible to adjust the curability and control the elastic modulus of the cured product without impairing the conformability of the thermosetting resin layer to irregularities.

As used herein, the term "volume average particle diameter" means a particle diameter (D50) at which the volume cumulative distribution curve is plotted from the small diameter side using a laser diffraction particle size distribution measuring apparatus and the cumulative 50%.

The content of the filler is, for example, 60 to 85% by mass based on the solid content of the thermosetting resin layer or the thermosetting resin composition for forming the same. This effectively suppresses the formation of voids in the hot-press sheet during heating and pressing (connecting step) for mounting electronic components. In addition, there is a tendency to obtain good moldability of the hot-press sheet. From the viewpoint of suppressing powder falling off, etc., the content of the filler is 65 to 75% by mass with respect to the mass of the solid content of the thermosetting resin layer or the thermosetting resin composition for forming it. good too.

Here, the solid content of the thermosetting resin composition refers to components other than water and volatile components such as solvents described later. The solid content includes those that are liquid or waxy at room temperature around 25° C., and is not necessarily solid. As used herein, volatile matter (i.e. water and solvent) means a substance with a boiling point of 200°C or less under atmospheric pressure. In the present specification, the content of each component in the thermosetting resin composition means the ratio based on the solid content of the thermosetting resin composition, unless otherwise specified.

The content of the filler based on the volume of the thermosetting resin layer or the solid content of the thermosetting resin composition is preferably 45 to 70% by volume, more preferably 50 to 60% by volume. preferable.

The volume-based content of the inorganic filler in the solid content of the thermosetting resin composition is measured as follows. First, the mass (Wc) of the solid content of the thermosetting resin composition at 25 ° C. is measured, and the thermosetting resin composition is heat-treated in the air at 400 ° C. for 2 hours and then at 700 ° C. for 3 hours. is burned off and the mass (Wf) of the remaining inorganic filler at 25°C is measured. Next, the specific gravity (df) of the inorganic filler at 25° C. is obtained using an electronic hydrometer or a hydrometer. Next, the specific gravity (dc) of the solid content of the thermosetting resin composition at 25°C is measured in the same manner. Then, the volume (Vc) of the solid content of the thermosetting resin composition and the volume (Vf) of the remaining inorganic filler are obtained, and the volume of the remaining inorganic filler is calculated as shown in (Equation 1) by the thermosetting resin. It is obtained as the volume ratio (Vr) of the inorganic filler by dividing by the volume of the solid content of the composition.

(Formula 1)
Vc=Wc/dc
Vf=Wf/df
Vr=Vf/Vc

Vc: Volume of thermosetting resin composition (cm ³ )
Wc: Mass (g) of thermosetting resin composition
dc: Density of thermosetting resin composition (g/cm ³ )
Vf: Volume of inorganic filler (cm ³ )
Wf: Mass of inorganic filler (g)
df: Density of inorganic filler (g/cm ³ )
Vr: Volume ratio of inorganic filler

Other Components The thermosetting resin layer and the thermosetting resin composition for forming the same contain photoinitiators such as photoradical polymerization initiators, photocationic polymerization initiators and photoanion polymerization initiators. good too.

When the thermosetting resin layer and the thermosetting resin composition for forming the same contain an epoxy compound as the thermosetting resin, the thermosetting resin layer and the thermosetting resin composition cure the epoxy compound. It may also contain a hardening agent that makes it harden. The curing agent is not particularly limited, and can be selected from commonly used curing agents. The curing agent may be solid or liquid, and a solid curing agent and a liquid curing agent may be used in combination. From the viewpoint of curing in a short time, it is preferable to use at least one kind of acid anhydride as a curing agent.

The equivalent ratio between the epoxy compound and the curing agent (functional group equivalent that reacts with the epoxy group) is not particularly limited. From the viewpoint of reducing the unreacted amount of each component, for example, the curing agent is preferably 0.1 to 2.0 equivalents, more preferably 0.5 to 1.25 equivalents, relative to the epoxy compound. is more preferred, and 0.8 to 1.2 equivalents is even more preferred.

When the thermosetting resin layer and the thermosetting resin composition for forming the same contain an epoxy compound as the thermosetting resin, the thermosetting resin layer and the thermosetting resin composition undergo a curing reaction of the epoxy compound. may contain a curing accelerator that accelerates the Examples of curing accelerators include phosphorus curing accelerators, amine curing accelerators, imidazole curing accelerators, and guanidine curing accelerators. Phosphorus curing accelerators, amine curing accelerators, and imidazole System curing accelerators are preferred. One of these curing accelerators may be used alone, or two or more thereof may be used in combination.

The content of the curing accelerator in the thermosetting resin layer and the thermosetting resin composition for forming the same is, for example, 0.05 when the total of the non-volatile components of the epoxy compound and the curing agent is 100% by mass. It is preferably ~3% by mass.

The thermosetting resin layer and the thermosetting resin composition for forming the same may contain at least one thermoplastic resin. Examples of thermoplastic resins include acrylic resins, styrene resins, butadiene resins, imide resins, and amide resins. These thermoplastic resins may be used alone or in combination of two or more.

Thermoplastic resins can be produced, for example, by radical polymerization of polymerizable monomers. Examples of polymerizable monomers include (meth)acrylic acid; (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, and benzyl (meth)acrylate; diacetone (meth)acrylamide; (meth)acrylamide such as; styrene or styrene derivatives such as styrene, vinyl toluene and α-methylstyrene; ethers of vinyl alcohol such as vinyl-n-butyl ether; maleic acid; fumaric acid; cinnamic acid; itaconic acid; and crotonic acid. These polymerizable monomers may be used singly or in combination of two or more. The thermoplastic resin may be an acrylic block copolymer formed by block copolymerization of at least one compound exemplified as a (meth)acrylate compound. As the thermoplastic resin, commercially available products may be used, and examples thereof include “Clarity LA series (LA-2140, LA-2250, LA-2330, LA-4285” manufactured by Kuraray Co., Ltd.).

As used herein, "(meth)acrylic acid" means acrylic acid or methacrylic acid, and "(meth)acrylamide" means acrylamide or methacrylamide.

The weight average molecular weight of the thermoplastic resin is preferably, for example, 5,000 to 1,000,000, more preferably 20,000 to 500,000, from the viewpoint of film-forming properties and fluidity.

The weight average molecular weight in this specification is a value measured by a gel permeation chromatography (GPC) method and converted by a calibration curve prepared using standard polystyrene. The conditions of GPC are shown below.
Pump: L-6000 type (manufactured by Hitachi, Ltd., trade name)
Column: Gelpack GL-R420 + Gelpack GL-R430 + Gelpack GL-R440 (total of 3 columns) (manufactured by Hitachi Chemical Co., Ltd., trade name)
Eluent: Tetrahydrofuran (THF)
Measurement temperature: 40°C
Flow rate: 2.05 mL / min Detector: L-3300 type RI (manufactured by Hitachi, Ltd., trade name)

The content of the thermoplastic resin in the thermosetting resin layer and the thermosetting resin composition for forming the same is, for example, 1 to 70% by mass in the total amount of the thermosetting resin layer and the thermosetting resin composition. and more preferably 5 to 50% by mass. When the content of the thermoplastic resin is 1% by mass or more, the film formability tends to be improved. When the content of the thermoplastic resin is 70% by mass or less, the curability tends to improve, and the bondability between the electronic component and the substrate tends to improve.

The thermosetting resin composition may contain at least one solvent. Solvents include, for example, methyl ethyl ketone, xylene, toluene, acetone, ethylene glycol monoethyl ether, cyclohexanone, ethyl ethoxypropionate, N,N-dimethylformamide, and N,N-dimethylacetamide. These solvents may be used individually by 1 type, and may use 2 or more types together.

The content of the solvent in the thermosetting resin composition is not particularly limited. For example, it is preferable to adjust the content according to the equipment for producing the resin sheet.

The thermosetting resin layer and the thermosetting resin composition for forming the same may contain other components as necessary. Other ingredients include, for example, solvents, coupling agents, colorants, surfactants, and ion trapping agents.

When the thermosetting resin composition is formed into a sheet, from the viewpoint of workability, the components of the thermosetting resin composition may be mixed in the aforementioned solvent to form a varnish. Alternatively, the obtained varnish may be applied onto a release sheet and dried to form a thermosetting resin layer.

Hot-press sheet manufacturing method The hot-press sheet 3 is formed by, for example, applying a varnish of a thermosetting resin composition containing the above-described thermosetting resin onto the release sheet 33a, and applying a thermosetting resin. It can be obtained by a method including drying a varnish of a resin composition to form a thermosetting resin layer 31 and laminating a release sheet 33 b on the thermosetting resin layer 31 .

The coating of the varnish on the release sheet 33a can be carried out by a normal method. Specific examples include methods such as comma coating, die coating, lip coating and gravure coating.

Drying of the varnish applied to the release sheet 33a is not particularly limited as long as at least part of the solvent contained in the varnish can be removed, and can be appropriately selected from commonly used drying methods. Instead of using varnish, a thermosetting resin composition whose fluidity is reduced by photoreaction may be applied to the release sheet 33a, and the applied thermosetting resin composition may be irradiated with ultraviolet rays. .

EXAMPLES The present invention will be specifically described below by way of examples, but the present invention is not limited to these examples.

<Production of hot press sheet>
Example 1
In a flask equipped with a stirrer, 196.6 g of an acrylic block copolymer (manufactured by Kuraray Co., Ltd., trade name "LA4285") as a thermoplastic resin, and trimethylolpropane triacrylate (Hitachi Chemical Co., Ltd. (Hitachi Chemical Co., Ltd.)) as a thermosetting resin. 98.32 g of FA137M, trade name, manufactured by NOF Corporation), 1.5 g of dicumyl peroxide (manufactured by NOF Corporation, trade name, Permil D) as a thermal radical polymerization initiator, and 1.5 g of dicumyl peroxide as a filler. 843.6 g of silica particles (manufactured by Admatechs Co., Ltd., trade name "SE2050", volume average particle size: 0.5 μm), and a hindered phenol-based polymerization inhibitor (manufactured by ADEKA Co., Ltd., trade name) as a polymerization inhibitor 0.075 g of "AO-60") and 288.5 g of methyl ethyl ketone as a solvent were added and mixed by stirring to obtain a varnish of a thermosetting resin composition. In this varnish, the content of the polymerization inhibitor was 0.08 parts by mass with respect to 100 parts by mass of the acrylate compound content, and the content of the filler was 73% by mass with respect to the mass of the solid content. .

The varnish of the thermosetting resin composition was applied to a polyimide film (manufactured by DuPont-Toray Co., Ltd., trade name “Kapton 100H”, average thickness: 25 μm) as a release sheet. The applied varnish was dried by heating for 10 minutes in a drier at 70° C. to form a thermosetting resin layer with an average thickness of 40 μm. A polyimide film (manufactured by Toray-DuPont Co., Ltd., trade name “Kapton 100H”, average thickness: 25 μm) is overlaid on the thermosetting resin layer, and a hot roll laminator is used at 100 ° C., 0.5 MPa, 1.0 m / A hot press sheet was obtained in which the polyimide film, the thermosetting resin layer and the polyimide film were laminated in this order.

Example 2
A varnish of a thermosetting resin composition was prepared in the same manner as in Example 1, except that the polymerization inhibitor was replaced with p-methoxyphenol (manufactured by Tokyo Chemical Industry Co., Ltd.), and a hot press sheet was produced. .

Comparative example 1
A varnish of a thermosetting resin composition was prepared in the same manner as in Example 1, except that no polymerization inhibitor was added, and a hot press sheet was produced.

<Manufacture of electronic component equipment>
As an electronic component, a silicon chip of 7.3 mm × 7.3 mm × 0.1 mm having aluminum wiring and bumps provided on the aluminum wiring (manufactured by Waltz Co., Ltd., trade name "WALTS-TEG CC80-0101JY-MODEL 1 , bump: Sn—Ag—Cu system, bump spacing: 80 μm). As a wiring board, a 18 mm × 18 mm × 0.4 mm board having a wiring layer and a solder resist (manufactured by Waltz Co., Ltd., trade name "WALTS-KIT CC80-0102JY-MODEL 1", solder resist: PSR4000-AUS703, base material : E679FGS) were prepared.

A film-like underfill material (manufactured by Hitachi Chemical Co., Ltd., epoxy-based NCF (Non-conductive Film)) is applied to the silicon chip heated to 80 ° C., and a diaphragm type vacuum laminator (Nikko Materials Co., Ltd. ), trade name “V130”).

A wiring board was placed on a stage, and a silicon chip was placed on a crimping head facing the stage so that the wiring layer of the wiring board and the bumps faced each other. Then, the temperature of the silicon chip was raised to 80° C., and the wiring board and the silicon chip were pressed with a load of 120 N by the stage and the temporary pressure bonding head, and the wiring layers of the wiring board and the bumps of the silicon chip were brought into contact with each other. . At this time, the underfill material provided on the silicon chip flowed under pressure, filling the gaps between the wiring substrate and the silicon chip between the aluminum wiring, the bumps and the wiring layer. Thus, five laminates were produced.

The five laminates were placed at the four corners and the center of a 10 cm square stage with the silicon chip facing upward. One hot press sheet of each example or comparative example was stacked so as to cover the five laminates on the stage. After that, the temperature of the pressure bonding head facing the stage was raised to 300° C., and the laminated body was heated and pressed with a load of 200 N for 10 seconds by the heated pressure bonding head and the stage. Thus, the wiring layer of the wiring substrate and the bumps of the silicon chip were electrically connected. In this way, five electronic component devices for evaluation were collectively manufactured. An electronic component device was manufactured using a hot-press sheet produced on the same day, or a hot-press sheet stored in a refrigerator for two weeks or four weeks after production.

For the obtained electronic component device, observation of peeling of the electronic component, confirmation of connectivity, confirmation of misalignment between the silicon chip and the wiring substrate, and confirmation of the presence or absence of voids in the hot-press sheet were carried out as follows. gone. Table 1 shows the evaluation results.

<Connectivity>
The continuity of the electronic component device was confirmed with a tester (manufactured by Kaise Co., Ltd., trade name "SK-6500"), and the connectivity was evaluated according to the following evaluation criteria.
-Evaluation criteria-
A: Continuity of electronic components is confirmed in all electronic component devices out of the five electronic component devices.
B: Conduction of electronic components is not confirmed in some of the five electronic component devices.

<Peeling off electronic components>
The inside of the electronic component device was observed using an ultrasonic observation device (manufactured by INSIGHT Co., Ltd., product name “INSIGHT-300”) to confirm the presence or absence of peeling of the electronic component. The peeling state of the electronic component was evaluated according to the following evaluation criteria.
-Evaluation criteria-
A: No peeling of the electronic component was observed in any of the five electronic component devices.
B: Peeling of the electronic component was observed in some of the five electronic component devices.

<Confirmation of misalignment between silicon chip and wiring board>
Regarding the electronic component device, the positional deviation in the surface direction between the bumps of the silicon chip and the wiring layer of the wiring board was measured using an X-ray observation device (manufactured by Nordson Advanced Technologies, Inc., trade name "XD-7600NT100-CT"). The positional deviation was evaluated according to the following evaluation criteria: The positional deviation was measured at 5 positions for each electronic component device, for a total of 25 positions for 5 electronic component devices, and the arithmetic mean value was obtained.
-Evaluation criteria-
A: The arithmetic mean value of misalignment is less than 7 μm.
B: Arithmetic average value of misalignment is 7 μm or more and less than 10 μm.
C: The arithmetic mean value of misalignment is 10 μm or more.

As shown in Table 1, by using a hot press sheet having a thermosetting resin layer containing a polymerization inhibitor, a plurality of electronic components can be produced while suppressing poor connection and peeling of electronic components even after a certain period of time. It was confirmed that component devices can be manufactured collectively.

DESCRIPTION OF SYMBOLS 1... Electronic component apparatus, 3... Sheet for hot press, 5... Laminated body, 10... Wiring substrate, 11... Insulating substrate, 13... Wiring layer, 20... Electronic component, 21... Body part of electronic component, 23... Electrode, 25... Bump, 30... Underfill material, 31... Thermosetting resin layer, 33a, 33b... Release sheet, 41... Stage, 42... Temporary pressure bonding head, 43... Pressure bonding head.

Claims (9)

A method of manufacturing an electronic component device comprising a wiring board and electronic components mounted on the wiring board, the method comprising:
A laminate comprising: an insulating substrate; a wiring substrate having a wiring layer provided on the insulating substrate; an electronic component having a plurality of electrodes; , and the bumps are interposed between the wiring layers and the electrodes facing each other. A step of electrically connecting the wiring layer and the electrode,
In the step of electrically connecting the wiring layer and the electrode, the laminate and the pressure bonding head are interposed with a hot press sheet having a thermosetting resin layer. is heated and pressurized,
The thermosetting resin layer contains a (meth)acrylate compound and a polymerization inhibitor,
The polymerization inhibitor contains a phenol-based polymerization inhibitor, the content of the polymerization inhibitor is 0.1 to 5 parts by mass with respect to 100 parts by mass of the (meth)acrylate compound content,
The thermosetting resin layer further contains a thermoplastic resin and a filler,
The filler contains silica particles, and the content of the filler is 60 to 85% by mass with respect to the mass of the thermosetting resin layer.
Method. 2. The laminate of claim 1, further comprising a thermosetting underfill material filling gaps between the electrodes, the bumps and the wiring layer between the electronic component and the wiring board. the method of. In the step of electrically connecting the wiring layer and the electrode, a plurality of the laminates each having one of the electronic components, or a plurality of the electronic components arranged on one of the wiring boards. 3. The method according to claim 1 or 2, wherein one or more of the laminates comprising the laminates are collectively heated and pressurized by being sandwiched between a set of the stage and the crimping head. In the step of electrically connecting the wiring layer and the electrode, the laminate is heated such that the temperature of the wiring substrate is 25 to 200° C. and the temperature of the electronic component is 230 to 300° C. A method according to any one of claims 1 to 3, wherein the pressure is applied. A laminate comprising: an insulating substrate; a wiring substrate having a wiring layer provided on the insulating substrate; an electronic component having electrodes; A laminated body, which is disposed and has bumps interposed between the wiring layer and the electrode facing each other, is sandwiched between a stage and a pressure bonding head to heat and pressurize the wiring layer and the electrode. A hot press sheet having a thermosetting resin layer used for interposing between the laminate and the compression head in the step of electrically connecting via the bumps,
The thermosetting resin layer contains a (meth)acrylate compound and a polymerization inhibitor,
The polymerization inhibitor contains a phenol-based polymerization inhibitor, the content of the polymerization inhibitor is 0.1 to 5 parts by mass with respect to 100 parts by mass of the (meth)acrylate compound content,
The thermosetting resin layer further contains a thermoplastic resin and a filler,
The filler contains silica particles, and the content of the filler is 60 to 85% by mass with respect to the mass of the thermosetting resin layer.
Sheet for heat press. 6. The hot press sheet according to claim 5, wherein the thermosetting resin layer has an average thickness of 10 [mu]m or more. 7. The hot press sheet according to claim 5, further comprising a release sheet provided on one side or both sides of said thermosetting resin layer. A thermosetting resin composition for hot press containing a (meth)acrylate compound and a polymerization inhibitor,
The polymerization inhibitor contains a phenol-based polymerization inhibitor, the content of the polymerization inhibitor is 0.1 to 5 parts by mass with respect to 100 parts by mass of the (meth)acrylate compound content,
The thermosetting resin composition further contains a thermoplastic resin and a filler,
The filler contains silica particles, the content of the filler is 60 to 85% by mass with respect to the mass of the solid content of the thermosetting resin composition,
A thermosetting resin composition for hot pressing, which is used to form a thermosetting resin layer of the sheet for hot pressing according to any one of claims 5 to 7. The thermosetting resin composition for hot press according to claim 8, further comprising a solvent.

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